Various types of pumps have been used to pump blood. Kovacs in U.S. Pat. No. 3,791,769 discloses a magnetically driven pump operable to produce pulsatile pumping action to pump blood in a human body. This pump has a pair of check valves that function in opposite directions to control the flow of blood into and out of the pumping chamber. Child in U.S. Pat. No. 3,835,475 discloses a pivoting disc heart valve having an annular base and a valving disc pivotally associated with respect to the base. Both the base and valving disc have coatings of Pyrolitic carbon. The pivoting disc heart valve operates in response to the natural pumping action of a heart to control the flow of blood in the heart.
Other types of blood pumps, including the bellows and collapsible bag blood pumps, are shown in U.S. Pat. Nos. 3,581,702; 3,568,214; 3,599,244; and 3,641,591.